1. Field of the Invention
The present invention relates to an image display device, and in particular, to an image display device having an image display means at which a plurality of image display media are arranged side-by-side.
2. Description of the Related Art
Liquid crystal display devices, which display images by simple matrix driving, have conventionally been known (refer to, for example, Patent Documents 1 through 3). The substrate of a simple matrix driving type image display medium is structured, for example, such that a display substrate 12, at which a plurality of linear row electrodes 161–16m as shown in FIG. 10A are provided, and a back surface substrate 14, at which a plurality of linear column electrodes 181–18n as shown in FIG. 10B are provided, are disposed so as to face one another and such that the row electrodes 161–16m and the column electrodes 181–18n are orthogonal to one another as shown in FIG. 11. The row electrodes 161–16m are driven by a row electrode driving circuit 32, and the column electrodes 181–18n are driven by a column electrode driving circuit 44.
When an image is displayed on an image display medium having such a simple matrix structure, a predetermined voltage is successively applied to the row electrodes 161–16m, and synchronously therewith, a predetermined voltage is applied to the column electrodes 18 corresponding to the line image of the row-line to which voltage is applied, such that the image is displayed line-by-line.
Moreover, a technique is known in which a plurality of these image display media are arranged side-by-side, so as to create a large screen (see, for example, Patent Documents 1, 2, 4). When forming a large screen by arranging a plurality of image display media side-by-side, utilizing a plurality of the same image display media is effective in terms of costs. For example, in the case of forming a large screen of two rows and two columns by using four image display media 10 as shown in FIG. 12, four display substrate portions 40, each of which is formed from the row electrode driving circuit 32 and the display substrate 12 shown in FIG. 10A, and four back surface substrate portions 52, each of which is formed from the column electrode driving circuit 44 and the back surface substrate 14 shown in FIG. 10B, are used, and are disposed such that all of the wires from the electrodes are led-out from the outer edge portion as shown in FIG. 12. Moreover, as shown in FIG. 13, the respective row electrode driving circuits 32A˜32D and column electrode driving circuits 44A–44D are controlled by a control section 62.
However, the following problem arises when forming a large screen by using the same display substrate portions 40 and back surface substrate portions 52 as described above. Namely, because the order of driving the electrodes at the display substrate portions 40 and back surface substrate portions 52 is determined in advance, as shown in FIG. 12, when the image display medium 10A is used as a reference, the order of the row electrodes 161–16m at the image display medium 10B is reversed, the order of the column electrodes 181–18n at the image display medium 10C is reversed, and the orders of both the row electrodes 161–16m and the column electrodes 181–18n at the image display medium 10D are reversed.
Accordingly, the problem arises that, as shown in FIG. 14 for example, when a Japanese character is displayed on each of the image display media 10A–10D, although the character is displayed normally at the image display medium 10A, the character is displayed upside down in terms of row order at the image display medium 10B, and is displayed with the left and right sides thereof reversed in terms of column order at the image display medium 10C, and is displayed upside down in terms of row order and with the left and right sides thereof reversed in terms of column order at the image display medium 10D.
Patent Document 1
Japanese Patent Application Laid-Open (JP-A) No. 11-133375
Patent Document 2
Japanese Patent Application Laid-Open (JP-A) No. 2001-242436
Patent Document 3
Japanese Patent Application Laid-Open (JP-A) No. 2001-66623
Patent Document 4
Japanese Patent Application Laid-Open (JP-A) No. 2002-139747